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1.
Plant Dis ; 98(11): 1577, 2014 Nov.
Article in English | MEDLINE | ID: mdl-30699823

ABSTRACT

At present, the principal bacterial disease of citrus in Brazil is Huanglongbing, caused by the alpha-proteobacterium 'Candidatus Liberibacter spp.' (although a phytoplasma of the 16SrIX group is also associated with this disease [4]). While there is a wide diversity of phytoplasmas in crop species in Brazil (3), there have been no reports of symptoms associated with phytoplasma in Brazilian citrus. Asymptomatic infections of citrus cannot be excluded as a possibility and such plants could serve as a reservoir of phytoplasma inoculum. The aim of this study was to assess the presence of phytoplasma in asymptomatic Citrus aurantifolia (acid lime) in Brazil. Thirty-three leaf samples (young leaves from the upper canopies) were randomly collected from different plants in the states of Minas Gerais (n = 23), Santa Catarina (n = 2), and São Paulo (n = 8). Two additional samples of C. limonia ('Rangpur' lime) and one of C. latifolia ('Persian' or 'Tahiti' lime) were collected in Minas Gerais. Total DNA extraction was performed using NucleoSpin Plant II Kit (Macherey-Nagel) according to the manufacturer's recommendations. PCR was carried out with a universal P1/P7 primer set followed by nested primers R16F2n/R16R2 (2). Additionally, direct PCR was performed using primers specific for phytoplasma immune-dominant membrane protein IMP3F/IMP3R (1). 'Rangpur' and 'Tahiti' lime were not infected with phytoplasma. Of the C. aurantifolia samples, 52% were positive for phytoplasma in the direct and nested PCR assays. The numbers of positive samples in Minas Gerais, Santa Catarina, and São Paulo states were 12, 1, and 4, respectively. Of these, five were selected for DNA purification and 1,246-bp fragments were ligated to the pGEM T-easy vector (Promega) and partial 16Sr DNA was sequenced. Nucleotide sequences of Brazilian phytoplasma strains BR:MG:FNS10:2011, BR:MG:FNS53:2011, BR:SP:FNS73:2011, BR:SC:FNS86:2011, and BR:MG:FNS126:2012 (GenBank Accession Nos. KJ158173, KJ158174, KJ158175, KJ158176, and KJ158177, respectively) were subjected to RFLP analyses. The 16S rDNA RFLP in silico patterns for the five strains were identical to each other and to Cactus witches'-broom phytoplasma (16SrII-C subgroup, AJ293216). In addition, the highest similarity coefficient (5) and nucleotide sequence identity of Brazilian phytoplasma strains were 0.99 and 99%, respectively, with Cactus witches'-broom phytoplasma. PCR-RFLP analyses using the enzymes Bstu I, EcoR I, and Hpa II were consistent with RFLP in silico results, showing the same pattern as the 16SrII-C subgroup. Phylogenetic analyses based on 16S rDNA sequences (1,246 bp) demonstrated that all the Brazilian strains grouped in the same clade with other representative sequences from the 16S rDNAII group. To confirm the absence of any macroscopic symptoms, morphological characteristics of 10 uninfected and 10 phytoplasma-infected plants randomly selected from a single field in Minas Gerais were analyzed. There were no significant differences in leaf area, stalk diameter, or numbers of leaves, flowers, or fruits per branch. To our knowledge, this is the first report of the 16SrII-C subgroup phytoplasma associated with C. aurantifolia in Brazil, and the first report of asymptomatic citrus plants infected with phytoplasma. References: (1) N. Askari et al. J. Microbiol. Biotechnol. 21:81, 2011. (2) I. M. Lee et al. Phytopathology 84:559, 1994. (3) H. G. Montano et al. Bull. Insectol. 60:129, 2007. (4) D. C. Teixeira et al. Phytopathology 98:977, 2008. (5) Y. Zhao et al. Meth. Mol. Biol. 938:329, 2013.

2.
Environ Entomol ; 41(2): 333-41, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22507006

ABSTRACT

Phytochemicals may modify the food quality, reduce a plant's palatability to insects, or defend against pests. This work aimed to study 1) relationships between the nitrogen and potassium levels given to plants in nutritive solutions and the foliar phytochemical concentrations, 2) the effect of nutrients and secondary compounds of Coffea arabica on the behavior of Coccus viridis, and 3) tolerance of C. arabica to losses. Deficient, normal, and excessive nitrogen and potassium fertilization treatments were used. Each treatment had two plants (one infested and one noninfested plant). The contents of phytochemicals in the infested plants' leaves and their dry matter of roots, stems, and leaves as well as the total contents in noninfested plants, were determined. The adults and nymphs of C. viridis were counted for 60 d in all treatments. It was verified that elevated nitrogen and potassium levels in the nutritional solutions led to increased of nymphs and adults of C. viridis to the coffee plants over time. Potassium and nitrogen had both direct and indirect effects on C. viridis. The direct effect was because of the increase of the nitrogen content in the leaves. The indirect effect instead was because of reductions in the caffeine and chlorogenic acid contents in the leaves. This is the first study to show relationship nutrient levels of coffee phytochemicals in response to herbivory by scale insects. Caffeine and chlorogenic acid applied on coffee leaves stimulated the locomotory activity of the green scale, thus reducing their feeding compared with untreated leaves. The elevation of caffeine and chlorogenic acid levels in coffee leaves affect this generalist insect by stimulating the locomotion of crawlers.


Subject(s)
Behavior, Animal/drug effects , Coffea/chemistry , Hemiptera/drug effects , Herbivory , Animals , Caffeine , Coffea/drug effects , Feeding Behavior/drug effects , Fertilizers , Food , Hemiptera/growth & development , Hemiptera/physiology , Nitrogen/metabolism , Plant Leaves/chemistry , Potassium/metabolism
3.
Transplant Proc ; 38(6): 1796-9, 2006.
Article in English | MEDLINE | ID: mdl-16908284

ABSTRACT

INTRODUCTION: The aim of this work was to study the effects of hyperbaric oxygenation as a preservation technique for small bowel transplantation. METHODS: Twenty 2-month-old male Wistar rats weighting 250 g were divided into two groups: group A (n = 10) in which the small bowel was preserved for 12 hours, and group B (n = 10) in which the small bowel was preserved for 24 hours. After vascular and intraluminal perfusion, 3-cm segments were maintained in Ringer's solution at temperatures between 2 degrees C to 4 degrees C and in normobaric O2 conditions (groups A1, B1) or conditioned in an hyperbaric O2 metal chamber (100% oxygen at 5.5 absolute atmospheres) (groups A2, B2). After this preservation time, we studied intestinal tissue injury and morphometric analysis of the villi. RESULTS: Mucosal injury was significantly greater among group A1 compared to group A2 animals. The grade of the lesions was greater among group B1 compared to group B2 animals. Group A1 showed no difference from Group B1. For lesion grade, the range was smaller in group A2 and group B2 animals. The villi height was significantly smaller in groups A1 and B1 compared to the other groups; whereas it was higher in group A2 as compared with B2. CONCLUSION: Hyperbaric oxygenation may play a role as a preservation technique. Further research is necessary.


Subject(s)
Hyperbaric Oxygenation/methods , Jejunum , Organ Preservation/methods , Animals , Hyperbaric Oxygenation/instrumentation , Intestinal Mucosa/pathology , Jejunum/pathology , Male , Microvilli/pathology , Models, Animal , Rats , Rats, Wistar
4.
Transplant Proc ; 38(6): 1876-8, 2006.
Article in English | MEDLINE | ID: mdl-16908311

ABSTRACT

UNLABELLED: This study was conducted to assess apoptosis and nuclear proliferation in rat small bowel submitted to hypothermic hyperbaric oxygenation for preservation. METHODS: Twenty two-month-old, male Wistar rats, weighing 250 g were divided into two groups: group I (n = 10), in which the small bowel was preserved for 12 hours, and group II (n = 10) in which the small bowel was preserved for 24 hours. After vascular and intraluminal perfusion, 3-cm segments were maintained in Ringer's solution at 2 degrees to 4 degrees C under normobaric conditions (groups Ia and IIa) or conditioned in a small hyperbaric metal chamber with 100% oxygen at 5.5 absolute atmospheres (groups Ib and IIb). After 12 or 24 hours, apoptotic and mitotic indices were evaluated by immunohistochemical methods. RESULTS: The apoptotic index was significantly higher in small bowel segments in groups Ia and IIa compared with groups Ib and IIb. The mitotic index was significantly higher among group IIb. CONCLUSION: Hypothermic hyperbaric oxygenation reduced intestinal epithelial apoptosis and increased nuclear proliferation during rat small bowel preservation.


Subject(s)
Apoptosis , Cell Nucleus/physiology , Cell Nucleus/ultrastructure , Intestine, Small/cytology , Intestine, Small/physiology , Organ Preservation/methods , Animals , Cell Division , Hyperbaric Oxygenation , Hypothermia, Induced , Intestinal Mucosa/cytology , Intestinal Mucosa/physiology , Male , Mitotic Index , Models, Animal , Rats , Rats, Wistar
5.
Transplant Proc ; 38(6): 1879-82, 2006.
Article in English | MEDLINE | ID: mdl-16908312

ABSTRACT

UNLABELLED: This study was designed to investigate the feasibility of building a simple and inexpensive device to preserve organs or tissues in hyperbaric and hypothermic conditions. METHODS: The device was built on a 40-cm wide, 28-cm long, and 23-cm deep stainless steel chassis. The pressure vessel was built by a 7.8-cm bore stainless steel cylinder put inside another 12-cm cylinder welded together and closed by a steel plate on the top and bottom. The inferior plate was welded, and the superior one was fixed by manual clasp nut. The cooling system is made up of air compressor, condenser, expansion area, and cooling worm that is located between the cylinders. The temperature-controlling device is a computer processor contained in an integrated-circuit chip, with a on-off system to maintain the chamber temperature between 2 degrees to 4 degrees C. The compression of the chamber is performed by lateral coupling with the oxygen cylinder and is maintained at 5.5 absolute atmospheres and controlled by air pressure gauge. The maximal work pressure was evaluated by spreadsheet. Temperature or pressure changes were evaluated by 12- and 24-hour assays. RESULTS: The maximal work pressure permitted was 6.5 absolute atmospheres. Thus, the container was free from danger. The temperature inside the chamber was kept between 2 degrees and 4 degrees C. The production costs of the prototype was US$1000. DISCUSSION: The manufacture of the refrigerating hyperbaric chamber is viable, simple, and inexpensive.


Subject(s)
Hyperbaric Oxygenation/methods , Organ Preservation/methods , Cold Temperature , Equipment Design , Hyperbaric Oxygenation/instrumentation , Organ Preservation/instrumentation , Refrigeration , Temperature
6.
Arq Neuropsiquiatr ; 54(4): 669-72, 1996 Dec.
Article in Portuguese | MEDLINE | ID: mdl-9201351

ABSTRACT

The authors report a case of cruciate hemiplegia associated with basilar impression, Chiari malformation and syringomyelia. The neuroanatomical controversy, the surgical treatment and the good outcome of the patient are discussed.


Subject(s)
Arnold-Chiari Malformation/complications , Hemiplegia/complications , Platybasia/complications , Syringomyelia/complications , Female , Hemiplegia/surgery , Humans , Middle Aged , Syringomyelia/surgery
7.
Arq Neuropsiquiatr ; 51(2): 281-4, 1993 Jun.
Article in Portuguese | MEDLINE | ID: mdl-8274096

ABSTRACT

The authors report a case of schistosomiasis mansoni with intraspinal localization on a 39 year old man who presented neurologic manifestation likely a Brown-Séquard syndrome. Cerebrospinal fluid examination showed positive immunofluorescent test for schistosomiasis, and treatment was started at once.


Subject(s)
Hemiplegia/etiology , Schistosomiasis mansoni/complications , Spinal Cord Diseases/etiology , Adult , Humans , Male , Schistosomiasis mansoni/physiopathology , Spinal Cord Diseases/physiopathology , Syndrome
8.
Arq. neuropsiquiatr ; 51(2): 281-284, 1993.
Article in Portuguese | LILACS | ID: lil-304948

ABSTRACT

The authors report a case of schistosomiasis mansoni with intraspinal localization on a 39 year old man who presented neurologic manifestation likely a Brown-Séquard syndrome. Cerebrospinal fluid examination showed positive immunofluorescent test for schistosomiasis, and treatment was started at once.


Subject(s)
Humans , Male , Adult , Spinal Cord Diseases/etiology , Hemiplegia , Schistosomiasis mansoni , Spinal Cord Diseases/physiopathology , Schistosomiasis mansoni , Syndrome
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